This invention pertains to auger-type devices adapted to move grain from the bottom of a grain bin into a center sump to be delivered commonly to an under bin auger from which the grain will be loaded onto a truck, wagon or the like to be moved.
Bins for the storage of grain now usually are of circular cross section so that unloading sweeps pivoted at the center of the floor can sweep fully across that cross section to move the grain from the bin. These sweeps normally use a special flighting to drive the grain to a central point where the grain moves into a conveyor to be delivered to a spot outside the bin. That outside spot is frequently an elevator designed to deliver the grain to a truck or wagon for removal of the grain from the premises.
In order to be effective, the sweep must move around the floor of the bin and is therefore ordinarily pivoted at the center and is driven circumferentially of the bin. That driving is accomplished usually by either a wheel at the end of the axle on which the fighting is mounted or by some sort of "walking" device mounted at the same location. Both of these expedients require substantial space at the end of the sweep and both have friction devices engaged with the floor of the bin in an area covered by grain. The wheel in particular may rotate at a speed in excess of its ability to move the sweep so there is constant wear of the material on the rim of the wheel.
By the present invention, applicant provides a friction wheel operating in a space recently cleared by the sweep. It is driven by a ratchet and pawl device to provide a forward speed more nearly approaching a speed at which the circumference of the drive wheel will maintain contact with the floor of the bin without constant skidding so that there is less wear on the rim of the wheel and more regular advancing of the sweep.